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Abstract Skin‐interfaced high‐sensitive biosensing systems to detect electrophysiological and biochemical signals have shown great potential in personal health monitoring and disease management. However, the integration of 3D porous nanostructures for improved sensitivity and various functional composites for signal transduction/processing/transmission often relies on different materials and complex fabrication processes, leading to weak interfaces prone to failure upon fatigue or mechanical deformations. The integrated system also needs additional adhesive to strongly conform to the human skin, which can also cause irritation, alignment issues, and motion artifacts. This work introduces a skin‐attachable, reprogrammable, multifunctional, adhesive device patch fabricated by simple and low‐cost laser scribing of an adhesive composite with polyimide powders and amine‐based ethoxylated polyethylenimine dispersed in the silicone elastomer. The obtained laser‐induced graphene in the adhesive composite can be further selectively functionalized with conductive nanomaterials or enzymes for enhanced electrical conductivity or selective sensing of various sweat biomarkers. The possible combination of the sensors for real‐time biofluid analysis and electrophysiological signal monitoring with RF energy harvesting and communication promises a standalone stretchable adhesive device platform based on the same material system and fabrication process.
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This content will become publicly available on July 17, 2027
Ultrasoft, adhesive, pH-tunable hydrogel based on in situ functionalized laser-induced graphene for through-hair concurrent biosensing
This work reports a printable, ultrasoft, highly stretchable, adhesive, breathable hydrogel engineered that is radically tuned by controlling the precursor pH level for simultaneous biosignal monitoring. The hydrogel based on porous laser-induced graphene composites synthesized using in situ laser reduction with polydopamine and tannic acid exhibits ultrasmall Young’s modulus of 1.08 kilopascal, super high stretchability of ~8000%, and desirable conductivity and adhesive strength for through-hair signal monitoring even in the presence of sweat. The excellent skin conformability of the hydrogel provides the resulting electrodes with low skin contact impedance at both wet and dry conditions, a high signal-to-noise ratio, and motion artifact–free monitoring of electrophysiological signals. Combined with electrodermal activity and strain sensing from the facile patterning/printing of the reusable and storable gel, the proof-of-concept demonstration of the device platform is showcased for anxiety monitoring and nerve rehabilitation studies.
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- Award ID(s):
- 2319139
- PAR ID:
- 10710307
- Publisher / Repository:
- Science
- Date Published:
- Journal Name:
- Science Advances
- Volume:
- 12
- Issue:
- 29
- ISSN:
- 2375-2548
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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